5% = 0.5
0.5n = 85
Divide by 0.5
0.5n = 85
/0.5 /0.5
n = 170.
The number is 170.
-7x + y = -6 |add 7x to both sides
y = 7x - 6
the slope: m = 7
the y-intercept: y = -6
Answer: choice A. 40 liters
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Explanation:
x = number of liters of the 50% alcohol solution
If we have x liters of 50% alcohol, then we have 0.50*x liters of pure alcohol. This is added to 0.90*40 = 36 liters of pure alcohol (from the 90% solution).
So far we have 0.50*x + 36. This expression represents the total amount of pure alcohol. We want a 70% solution, so we want 70% of the total 40+x meaning 0.50*x + 36 is to be set equal to 0.70*(40+x) and we solve for x as shown below
0.50*x + 36 = 0.70*(40+x)
0.50*x + 36 = 0.70*(40)+0.70*(x)
0.50*x + 36 = 28+0.70*x
36 - 28 = 0.70*x - 0.50x
8 = 0.20x
0.20x = 8
x = 8/0.20
x = 40
So that is why the answer is choice A. 40 liters
Answer:
Range=65
Step-by-step explanation:
The highest is 66 the lowest is 1 so 66-1=65
